Bug 1138417: sql_group_concat() generates bad SQL code with PostgreSQL 8.x

Bugzilla/DB/Pg.pm

@@ -85,6 +85,15 @@ sub sql_group_concat {
     $sort = 1 if !defined $sort;
     $separator = $self->quote(', ') if !defined $separator;
 
+    # PostgreSQL 8.x doesn't support STRING_AGG
+    if (vers_cmp($self->bz_server_version, 9) < 0) {
+        my $sql = "ARRAY_ACCUM($text)";
+        if ($sort) {
+            $sql = "ARRAY_SORT($sql)";
+        }
+        return "ARRAY_TO_STRING($sql, $separator)";
+    }
+
     if ($order_by && $text =~ /^DISTINCT\s*(.+)$/i) {
         # Since Postgres (quite rightly) doesn't support "SELECT DISTINCT x
         # ORDER BY y", we need to sort the list, and then get the unique
@@ -102,11 +111,6 @@ sub sql_group_concat {
         $order_by = " ORDER BY $1";
     }
 
-    if (vers_cmp($self->bz_server_version, 9) < 0) {
-        # PostgreSQL 8.x doesn't support STRING_AGG
-        return "ARRAY_TO_STRING(ARRAY_AGG($text$order_by), $separator)";
-    }
-
     return "STRING_AGG(${text}::text, $separator${order_by}::text)"
 }
 
@@ -234,7 +238,37 @@ sub bz_setup_database {
     my ($has_plpgsql) = $self->selectrow_array("SELECT COUNT(*) FROM pg_language WHERE lanname = 'plpgsql'");
     $self->do('CREATE LANGUAGE plpgsql') unless $has_plpgsql;
 
-    # Custom Functions
+    if (vers_cmp($self->bz_server_version, 9) < 0) {
+        # Custom Functions for Postgres 8
+        my $function = 'array_accum';
+        my $array_accum = $self->selectrow_array(
+            'SELECT 1 FROM pg_proc WHERE proname = ?', undef, $function);
+        if (!$array_accum) {
+            print "Creating function $function...\n";
+            $self->do("CREATE AGGREGATE array_accum (
+                           SFUNC = array_append,
+                           BASETYPE = anyelement,
+                           STYPE = anyarray,
+                           INITCOND = '{}' 
+                       )");
+        }
+
+       $self->do(<<'END');
+CREATE OR REPLACE FUNCTION array_sort(ANYARRAY)
+RETURNS ANYARRAY LANGUAGE SQL
+IMMUTABLE STRICT
+AS $$
+SELECT ARRAY(
+    SELECT $1[s.i] AS each_item
+    FROM
+        generate_series(array_lower($1,1), array_upper($1,1)) AS s(i)
+    ORDER BY each_item
+);
+$$;
+END
+    }
+    else {
+        # Custom functions for Postgres 9.0+
 
         # -Copyright © 2013 Joshua D. Burns (JDBurnZ) and Message In Action LLC
         # JDBurnZ: https://github.com/JDBurnZ
@@ -282,6 +316,7 @@ sub bz_setup_database {
             END;
             $BODY$ LANGUAGE plpgsql;
         |);
+    }
 
     # PostgreSQL doesn't like having *any* index on the thetext
     # field, because it can't have index data longer than 2770